Traditionally, an engine oil pump sucks up oil stored in an oil housing through a strainer and sends it to a circuit, for example an engine lubricating circuit. The oil housing also cooperates with recycling means making it possible to recover excess oil and transfer it again to the oil housing so as to again be sucked up by the oil pump. The strainer thus fulfils the role of an oil filter; it filters the impurities of the oil so as to stop them from penetrating the oil pump. The strainer is immersed in the oil housing.
Some engines, such as the SMA SR305-230 engine, are equipped with an association of two pumps sucking up oil in the same housing. Each pump cooperates with a circuit, for example in the case of the SMA SR305-230 engine, a lubricating circuit and a cooling circuit. Traditionally, the oil returns via a screen to the strainer of the housing, where it is sucked up by the two pumps.
FIG. 1 shows an exploded view of an oil filtering and distributing device 1 for an association of two pumps according to the prior art. The device 1 comprises a casing 12 formed of a lower part 10 and an upper part 11. The lower part 10 comprises an aperture in which a circular screen 13 is installed. The upper part 11 comprises a first aperture 14 and a second aperture 15 in which a first sleeve coupling 16 and a second sleeve coupling 17 are fitted. The first sleeve coupling 16 and the second sleeve coupling 17 are connected to the two pumps. The oil penetrates the housing 12 via the screen 13. It is sucked up there by the two pumps.
Such a device has proven to be satisfactory if the two pumps operate at the same flow rate. Otherwise, the pump having the stronger flow rate interferes with the pump having the weaker flow rate by starving the pump having the weaker flow rate. The oil pump having a weaker flow rate is thus deprimed, possibly resulting in destruction of the engine. Such a problem is currently encountered in some engines in which the flow rate of the pump associated with the lubricating circuit and the pump associated with the cooling circuit have to be operated at different flow rates.